This site works best with JavaScript enabled!

Description: Random Generator - Random String

Random Generator String

On this page the algorithm of the "Random String" generator is described. This generator creates a random string. You can set the desired length of the string and choose whether uppercase letters, lowercase letters, numbers and / or special characters should be included.

Random generator "Random String"

Click here to go to the random generator described below.

What is randomness?

Randomness is an event for which there is no causal explanation. This means that the result of a random generator may not be predictable or computable. This, however, contradicts the laws of each computer. In other words, a computer can not produce absolutely random numbers without additional peripherals. In this case we call it pseudo-random numbers. In general, you can philosophize about at which point you can actually speak about randomness.

How are the random strings generated?

Theoretically, three different mechanisms for generating pseudo-random numbers are used in this generator, but two of them are only used to generate the binary string in the background.

Random generator 1 and 2 for binary string

How these random generators work, is explained here in detail.

Random generator 3 for random string

The previous random number generators produce relatively good random numbers, which, however, can further be improved. The strings are therefore always generated on server-side with the PHP function random_int(), which generates cryptographically secure pseudo-random numbers:

// The variable $all_chars contains all chosen characters
$max_index 	= count($all_chars)-1;
$random_answer 	= "";

// Generate string
for($i = 1; $i <= STRING_LENGTH; $i++) {
	$index = random_int(0, $max_index);
	$random_answer .= $all_chars[$index];
Share this page
Posted on 16.12.2016 | Last modified on 16.01.2018